The search for additional oil and gas has turned to deeper underwater locations. Virtually all commercial offshore production is in water less than three hundred feet deep, but plans are going forth for drilling for oil and gas to water depths of greater than 1,000 feet. Various types of drilling platforms have been suggested of various configurations. The design most widely used is the fourleg design having provisions for drilling multiple wells therefrom and which is generally floated to the drill site and secured in place to the underwater floor. However, such platforms are extremely expensive, costing millions of dollars, require a considerable amount of lead time to construct, and once secured in place, cannot readily be modified to meet changing conditions which may be required depending upon the drilling conditions encountered.
The present invention is directed to a modular underwater well drilling platform in which the modules are connected to the underwater floor only when needed and the location and size of the platform is not committed until the field size and location is defined. The modular structure of the present invention offers maximum flexibility with a minimum of cost. The various modular units can be manufactured at different locations to cut down on lead time, the modular units can be made up and stocked for future use, the configuration of the platform can be put together in modular form to meet the varying needs as they are encountered in day-to-day operations, and the modular configuration permits expansion of the platform as conditions dictate at a later date.